This invention relates to a diffuser component for a gas turbine.
Using a diffuser component of this type, a fluid flow in the direction of a combustion chamber of a gas turbine, in particular of a gas-turbine engine, can be slowed down, where a flow cross-section of the diffuser component is widened to do so. The flow cross-section of the diffuser component is defined here by a diffuser wall which extends from an inlet of the diffuser component in the direction of an outlet of the diffuser component, such that the flow cross-section widens continuously or non-continuously in the direction of the outlet.
Inside a gas-turbine engine, a diffuser component of this type forms for example part of an axial diffuser at the end of a (high-pressure) compressor downstream of an outlet guide vane. The diffuser component is here typically connected upwards to a combustion chamber casing and a compressor casing, and downwards to an inner combustion chamber casing. Starting from the outlet of the diffuser component, air then flows in particular to a combustion chamber of the gas-turbine engine and here, for example, to a combustion chamber flame tube defining a combustion space.
Usually, the diffuser wall is at most locally connected to the combustion chamber casings and to the compressor casing. A part of the diffuser wall is thus not supported on the respective casing. At least one section of the diffuser component can also project with its diffuser wall into the combustion chamber. It can thus occur during operation of the gas turbine that the diffuser wall starts to vibrate. Vibration of this type can however in some circumstances lead to tearing away of part of the diffuser wall during operation.
An increase in the strength, and in particular in the fatigue strength, of the diffuser component by designing the diffuser wall with an increased wall thickness is as a rule not desirable here. On the one hand, the possibility for an increased thickness may be limited by the installation space available, and on the other hand, an increased thickness would considerably increase the weight of the diffuser component.